We turn to the desperate search to identify what could be tens of thousand of people infected with the deadly disease. The alleged culprit a medical technician that worked in 13 hospitals in 8 states. David kerley joins us with all of the details. David. Good morning. Already more than 2 dozen cases of infection of help citis b have been traced to this man, according to law enforcement. Because he's a traveling fill-in hospital worker, there's a fear that many more could have contracted this disease which could lead to serious liver problems. He's been called a serial infector, an unprecedented case. He's poisoned 30 people and we don't know the pre vice numbers elsewhere. Reporter: That's because david inspected with hepatitis c was a traveling medical technician. In new hampshire, he's charged with stealing drugs in a syringe, injecting himself, refilling the now contaminated syringe with another liquid which was then used on a patient. If he knew he was infected and put those needles on the shelf that's the definition of evil. Reporter: The fear is he may have committed the same crime elsewhere. In the past 5 years, he's worked in 13 hospitals in 8 states, from maryland to arizona, georgia to new york. All scrambling to identify more potential victims of this frightening crime. In new hampshire alone. Officials called 4,000 people to get tested. Potentially I could be infected. The unknown is the scary part because you know there's some serious treatment. Reporter: But a clinic scheduled this weekend is canceled. The state overwhelmed by the logistic a case that left dozens knowing about serious health issues. Reporter: When arrested, they think he may have been contemplating suicide. They saw a note there. It's may be difficult to trace to older cases because after a year it mutates making it difficult to track. Sharyn. Frightening stuff. Thank you, david from washington

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